Many microorganisms and also eukaryotic cells excrete typical cytoplasmic proteins. As none of the classical secretion systems appears to be involved, this type of secretion has been referred to as "non-classical protein secretion". So far it is neither known by which mechanism nor why cytoplasmic proteins are excreted. Our research is concentrated on why, how, where and when staphylococci excrete cytoplasmic proteins.

Our preliminary results have shown that in Staphylococcus aureus more than 20 typical cytoplasmic proteins were excreted and that the excretion of cytoplasmic proteins already starts in the exponential phase and appears to be more pronounced in the clinical isolates than in the non-pathogenic staphylococcal species. We could show that there is no correlation between the quantity of cytoplasmic proteins in the cytoplasm and their release to the extracellular environment. We assume that there exists a selection procedure in the excretion of cytoplasmic proteins. We want to address the question why microorganisms excrete cytoplasmic proteins, which is a loss of resources and energy. Is the excretion of such proteins an accident or is it intentional?

Referenzces:

1. Ebner, P., A. Luqman, S. Reichert, K. Hauf, P. Popella, K. Forchammer, M. Otto & F. Götz (2017) Non-classical Protein Excretion Is Boosted by PSMα-Induced Cell Leakage. Cell Rep. 20(6):1287-1286
2. Ebner P., J. Rinker, MT. Nguyen, P. Popella, M. Nega, A. Luqman, B. Schittek, M. Di Marco, S. Stevanovic & F. Götz, (2016) Excreted Cytoplasmic Proteins Contribute to Pathogenicity in Staphylococcus aureus. Infect Immun. [Pubmed]
3. Ebner, P., J. Rinker & F. Götz, (2015) Excretion of cytoplasmic proteins in Staphylococcus is most likely not due to cell lysis. Current Genetics [Springer Link]
4. Ebner, P., M. Prax, M. Nega, I. Koch, L. Dube, W. Yu, J. Rinker, P. Popella, M. Flötenmeyer & F. Götz, (2015) Excretion of cytoplasmic proteins (ECP) in Staphylococcus aureus. Molecular Microbiology [Wiley Online Library]
5. Götz F., W. Yu, L. Dube, M. Prax & Patrick Ebner, (2015) Excretion of cytosolic proteins (ECP) in bacteria. International Journal of Medical Microbiology [ScienceDirect]
6. Pasztor, L., A. K. Ziebandt, M. Nega, M. Schlag, S. Haase, M. Franz-Wachtel, J. Madlung, A. Nordheim, D. E. Heinrichs & F. Götz, (2010) Staphylococcal major autolysin (atl) is involved in excretion of cytoplasmic proteins. J Biol Chem 285: 36794-36803. [PubMed]
7. Nega, M., L. Dube, M. Kull, A-K. Ziebandt, P. Ebner, D. Albrecht, B. Krismer, R. Rosenstein, M. Hecker & F. Götz, (2014) Secretome analysis revealed adaptive and non-adaptive responses of the Staphylococcus carnosus femB mutant. Proteomics: Accepted manuscript online: 28 November 2014. [Proteomics]

For more information please contact

Dr. Patrick Ebner

Phone: +49 (7071) 29- 77617

patrick.ebner[at]uni-tuebingen.de